How to aspirate the correct volume using a pipette filler?

Serological or volumetric pipettes are the traditional and convenient mode of liquid transfer in milliliters from reservoirs with either small diameters or long necks, by minimizing the chances of cross-contamination.

These can be disposable or autoclavable. To draw liquid into a serological pipette, traditionally mouth pipetting was preferred, where the liquid was being drawn using the suction created by mouth. This technique has been banned worldwide due to the serious health risks associated with this. To overcome this, pipette controllers were introduced.

A pipette filler also referred to as a pipette controller or pipette aid, is a handheld device commonly utilized in laboratories for aspirating and dispensing liquids using a serological pipette. Its purpose is to simplify the pipetting process by offering a comfortable grip, precise control, and easy operation.

A pipette filler typically consists of the following components:

Handheld Unit: The main part of the pipette filler is a handheld device that the user holds during the pipetting process. It usually has a comfortable grip and ergonomic design for ease of use.

Collet Assembly: The pipette filler comes with an in-built collet assembly. This collet assembly securely holds the serological pipette in place during pipetting.

Power Source: The device is powered by rechargeable batteries or through a direct power supply.

Control Plungers: The handheld unit has control plungers that allow the user to aspirate and dispense liquids with precision. By pressing the upward plunger (look for the ‘up’ mark), the liquid is aspirated into the serological pipette and downward plunger (look for the ‘down’ mark) to dispense the liquid into the container.

Thumb Wheel: A thumb wheel on the instrument’s back allows for easy pump speed adjustments during liquid handling. Users can rotate the wheel clockwise to increase pump speed and anticlockwise to decrease pump speed. 

Using a pipette filler is relatively straightforward. By pressing the control plunger, the user can aspirate a specific volume of liquid into the serological pipette and then dispense it into the desired location.

The pipette filler offers advantages over manual pipetting, such as increased accuracy, reduced risk of repetitive strain injuries, and enhanced user comfort during prolonged pipetting sessions. It is an indispensable tool in modern laboratories where precision and efficiency are paramount in handling liquid samples.

Aspirating the correct volume using a Pipette Filler

The primary application of any electronic filler/controller is to enable lab users to precisely fill a serological pipette to a certain specific volume and dispense that aspirated volume of liquid into a container for their experiments. However, pipette controllers in the market do not provide any direct mechanism for the lab user to precisely aspirate and dispense a required volume. The methods employed by lab users to achieve this are inaccurate and time-consuming. Users have to either: 

1. Manipulate the speed controller of the pipette filler to precisely fill gently up to the desired volume 
2. Fill more than the required volume and dispense slowly (using gravity) to achieve the desired volume

Aspirating and dispensing liquid accurately with a pipette filler requires proper technique and familiarization with the device’s controls. Here’s a step-by-step guide to help you use an electronic pipette filler accurately:

Preparation:

• Ensure the pipette filler is charged or has sufficient power for your pipetting task.
• Select the appropriate serological pipette and attach it securely to the electronic pipette filler.

Aspirating the Liquid:

• Immerse the tip of the serological pipette into the liquid sample you want to aspirate.
• Gently press and hold the aspiration plunger of the pipette filler. Make sure you don’t aspirate beyond the maximum volume capacity of the serological pipette.
• Aspirate the liquid more than the required liquid. For instance, if you want to dispense 20 ml liquid, aspirate the 25 ml liquid to begin with.
• Dispense excessive liquid (5ml extra as per the above example) gently until the liquid meniscus aligns with the required mark on the serological pipette. 

Most of the pipette fillers have the Gravity Dispense feature by which the user can dispense the liquid in drops by pressing the dispense button. This feature does not engage the motor and allows the user to dispense the liquid dropwise and slowly which increases the dispensing accuracy.

Dispensing the Liquid:

• Position the pipette slightly above the surface of the target container (e.g., microplate well, test tube, etc.).
• Gently press and hold the dispensing plunger on the pipette filler to release the liquid. Control the speed of dispensing as needed by rotating the thumb wheel clockwise or anti-clockwise. The liquid will flow out of the pipette due to gravity. 

Blow-out Function (Optional):

Some pipette fillers have a blow-out function that expels any remaining liquid in the serological pipette’s tip after dispensing. If your pipette filler has this feature, you can activate it by pressing the corresponding button.

Release the Buttons:

Once you’ve dispensed the desired volume, release the plungers on the pipette filler to stop the liquid flow.

Release the Liquid:

After dispensing, wait for a brief moment before withdrawing the pipette from the liquid to avoid any residual drops on the serological pipette’s tip.

Discard or Retain the Tip:

Depending on the application and your laboratory’s protocols, you may need to discard the used serological pipette after each aspiration-dispensing cycle or retain it for further use (if compatible with your procedures).

Always follow the manufacturer’s guidelines and proper laboratory practices to ensure accurate and reliable pipetting results. Regularly calibrate and maintain the pipette filler for optimal performance.

Microlit Easyfill – Electronic Pipette Filler with Single Knob Dual Dispensing Mode

Microlit Easyfill is a highly dependable pipette filler that has several features that contribute to precise volume aspiration, such as:

• Hold Pipettes Firmly with a Universal Silicon Collet Adapter:

Microlit Easyfill features a Universal Silicon Adapter with internal knurling that can easily accommodate pipettes ranging from 1 ml to 100 ml and securely hold them during liquid handling operations.

• Comfortable Grip:

Designed with a focus on ergonomics, Microlit Easyfill boasts a comfortable grip. This thoughtful design reduces hand fatigue and strain during extended pipetting procedures, promoting better posture and minimizing the risk of repetitive strain injuries.

• Prevention of Contamination:

Microlit Easyfill includes a PTFE Hydrophobic In-line Membrane Filter (0.2 microns), which prevents aerosol contamination from an accidental liquid entry. As a result, it ensures aseptic conditions and reduces the risk of cross-contamination between different samples.

• Speed and Efficiency:

Microlit Easyfill offers continuous pump speed adjustment during liquid handling operations. The efficient performance of Microlit Easyfill enables quick and precise liquid handling. Its user-friendly design and rapid dispensing speed allow researchers to complete pipetting tasks more efficiently, ultimately increasing overall productivity.

• Battery-Powered Operation with LED Indicator:

Many versions of Microlit Easyfill are powered by batteries, offering cordless operation. This feature enhances mobility and flexibility, enabling researchers to move freely in the laboratory without being hindered by power cords. It has a Red LED flash that denotes ‘low battery’ and a green LED flash that denotes ‘charging’.

• Precise Gravity Dispense Mode:

To dispense drops dropwise, turn the knob halfway. This option disables the motor and allows the user to dispense dropwise and slowly.

• User-Friendly Interface:

Microlit Easyfill is designed to be intuitive and user-friendly, making it suitable for both experienced researchers and laboratory newcomers. The instrument’s easy operation allows users to quickly adapt and efficiently perform pipetting tasks.

To know more about the features and functionality of Microlit Easyfill, please contact us at info-usa@microlit.com or visit our website Microlit Pipette Filler.